In recent years, image display devices have been developed so as to display a three-dimensional image as well as a two-dimensional image.
An example of an image display device that is capable of displaying a three-dimensional image is disclosed in Korean Patent Application Publication No. 10-2012-0069372 entitled MULTILAYER DISPLAY DEVICE.
A conventional multilayer display device includes a first display panel for displaying a rear image, a first light source disposed at one surface of the first display panel for providing light, a second display panel disposed on the other surface of the first display panel for displaying a front image, and a second light source disposed on at least one surface of the second display panel for providing light that corresponds to the luminance of the first display panel.
In the conventional multilayer display device having the above construction, the image displayed by the first display panel and the image displayed by the second display panel overlap each other in order to provide a three-dimensional image to viewers.
In the conventional multilayer display device, however, the transmissivity of the display panels is less than 10%. The light source is additionally mounted between the first display panel and the second display panel, which overlap each other, such that the second display panel, which is located at the rear, has sufficient brightness to be clearly viewed. As a result, power consumption is excessive, and the light source is rapidly aged due to the generation of heat from the light source.
In addition, the luminance of the second display panel, which is disposed at the rear, is further increased by the light source mounted between the second display panel and the first display panel, whereby it is difficult to display a clear image.